Services at Bus Éireann are at a standstill for a third day.
The ongoing row centres on cost cutting measures by the company.
Bus Éireann says the strike action is costing it tens of thousands of euro in losses every day.
Solidarity TD Mick Barry says it is impossible to run a modern public transport system on a shoestring.
"The subvention for Bus Éireann is 20% down on where it was eight years ago, it's not a credible position from the Government.
"If you do it on a shoestring it's either low pay for the workers, high fares for the customers, or very poor service. This it the 21st century, we need proper funding of public transport," he said.